Repurposing auranofin for the treatment of cutaneous staphylococcal infections

Int J Antimicrob Agents. 2016 Mar;47(3):195-201. doi: 10.1016/j.ijantimicag.2015.12.016. Epub 2016 Jan 23.


The scourge of multidrug-resistant bacterial infections necessitates the urgent development of novel antimicrobials to address this public health challenge. Drug repurposing is a proven strategy to discover new antimicrobial agents; given that these agents have undergone extensive toxicological and pharmacological analysis, repurposing is an effective method to reduce the time, cost and risk associated with traditional antibiotic innovation. In this study, the in vitro and in vivo antibacterial activities of an antirheumatic drug, auranofin, was investigated against multidrug-resistant Staphylococcus aureus. The results indicated that auranofin possesses potent antibacterial activity against all tested strains of S. aureus, including meticillin-resistant S. aureus (MRSA), vancomycin-intermediate S. aureus (VISA) and vancomycin-resistant S. aureus (VRSA), with minimum inhibitory concentrations (MICs) ranging from 0.0625μg/mL to 0.125μg/mL. In vivo, topical auranofin proved superior to conventional antimicrobials, including fusidic acid and mupirocin, in reducing the mean bacterial load in infected wounds in a murine model of MRSA skin infection. In addition to reducing the bacterial load, topical treatment of auranofin greatly reduced the production of inflammatory cytokines, including tumour necrosis factor-α (TNFα), interleukin-6 (IL-6), interleukin-1 beta (IL-1β) and monocyte chemoattractant protein-1 (MCP-1), in infected skin lesions. Moreover, auranofin significantly disrupted established in vitro biofilms of S. aureus and Staphylococcus epidermidis, more so than the traditional antimicrobials linezolid and vancomycin. Taken together, these results support that auranofin has potential to be repurposed as a topical antimicrobial agent for the treatment of staphylococcal skin and wound infections.

Keywords: Auranofin; Inflammatory cytokines; Multidrug resistance; Repurposing; Topical antimicrobials.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Anti-Bacterial Agents / therapeutic use*
  • Auranofin / therapeutic use*
  • Biofilms / drug effects
  • Cell Line
  • Chemokine CCL2 / biosynthesis
  • Drug Repositioning*
  • Drug Resistance, Multiple, Bacterial
  • Drug Therapy, Combination
  • Female
  • Fusidic Acid / therapeutic use
  • Humans
  • Interleukin-1beta / biosynthesis
  • Interleukin-6 / biosynthesis
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Mice
  • Mice, Inbred BALB C
  • Microbial Sensitivity Tests
  • Mupirocin / therapeutic use
  • Staphylococcal Skin Infections / drug therapy*
  • Staphylococcal Skin Infections / microbiology
  • Staphylococcus epidermidis / drug effects*
  • Tumor Necrosis Factor-alpha / biosynthesis


  • Anti-Bacterial Agents
  • Ccl2 protein, mouse
  • Chemokine CCL2
  • IL1B protein, mouse
  • Interleukin-1beta
  • Interleukin-6
  • Tumor Necrosis Factor-alpha
  • Auranofin
  • Fusidic Acid
  • Mupirocin